[en] Theoretical studies are reported of the following aspects of charge distribution: the deformation density, defined as the difference between the total density and the density in the promolecule or procrystal, which is the superposition of free atoms centred at the nuclear positions; and the valence density, which is the function obtained theoretically as the total density in calculations in which core electrons are represented by a model potential. Charge distribution in (a) crystalline silicon, (b) beryllium metal, (c) vanadium metal, and (d) the A 15 alloys V₃Si and Cr₃Si, is discussed. (U.K.)